An intervertebral spacer and stabilization implant includes a plate having sockets configured for retaining a fastener passable through the socket and into an adjacent vertebral body. One or more connecting projections extend from a side of the plate, to mate with projections extending from a spacer body. A plurality of teeth project from at least one of the upper or lower surfaces of the spacer body, and a chamber is formed through the spacer body to enable bone fusion between the vertebrae. The combined plate and spacer may be inserted to lie completely within the intervertebral space, or a portion of the plate may overlie a vertebral body.